External high pressure pump and filter between the tank and pump replaces the in tank components.
Recently the fuel pump in my 3 year old Yamaha Cygnus scooter became unreliable. As it had only done just over 6,000km I was not very happy and decided to contact the dealer I purchased it from. They denied knowing of any problem with the Cygnus EFI fuel pump and quoted a cost of $350 for the supply of a replacement. Since my hours of “Googling” had led me to many posts about the same problem with the Cygnus and the Maxi (same pump in both models) I was not prepared to buy a new pump and risk only getting another measly 6,000km before it too packed up.
Relay in top left to control power to the pump and to avoid frying the engine ECU. Fuel return hose on the right connected to the tank.
Rest assured I would not purchase another Yamaha product knowing they are prepared to use a poor quality component and then deny the problem or offer any support.
Since I was left with an unusable scooter I decided to convert the fuel supply system using less costly (and more reliable) EFI components intended for cars. Is that possible – yes it is. Â I have done it and the scooter now runs like a new one. Not only should it be more reliable, I saved a $100 and should a part fail in the future I will not have to replace a complete fuel tank module just because a crappy quality Yamaha pump has failed. My new system is completely modular meaning each part can be changed out individually for a smidgen of the cost.
Fuel pressure regulator (gold component) set at 2.5 bar.
Finally, the power supply for the pump protected with a blade fuse (red cover)
I have included some photos of the new fuel supply; both low and high pressure parts of the system are non Yamaha.
Would you like more information – please make the request in the comments section.
Yamaha Cygnus Fuel Pump Problem.
